'\" et
.TH AIO_SUSPEND "3P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual"
.\"
.SH PROLOG
This manual page is part of the POSIX Programmer's Manual.
The Linux implementation of this interface may differ (consult
the corresponding Linux manual page for details of Linux behavior),
or the interface may not be implemented on Linux.
.\"
.SH NAME
aio_suspend
\(em wait for an asynchronous I/O request
.SH SYNOPSIS
.LP
.nf
#include <aio.h>
.P
int aio_suspend(const struct aiocb *const \fIlist\fP[], int \fInent\fP,
    const struct timespec *\fItimeout\fP);
.fi
.SH DESCRIPTION
The
\fIaio_suspend\fR()
function shall suspend the calling thread until at least one of the
asynchronous I/O operations referenced by the
.IR list
argument has completed, until a signal interrupts the function, or, if
.IR timeout
is not NULL, until the time interval specified by
.IR timeout
has passed. If any of the
.BR aiocb
structures in the list correspond to completed asynchronous I/O
operations (that is, the error status for the operation is not equal to
.BR [EINPROGRESS] )
at the time of the call, the function shall return without suspending
the calling thread. The
.IR list
argument is an array of pointers to asynchronous I/O control blocks.
The
.IR nent
argument indicates the number of elements in the array. Each
.BR aiocb
structure pointed to has been used in initiating an asynchronous
I/O request via
\fIaio_read\fR(),
\fIaio_write\fR(),
or
\fIlio_listio\fR().
This array may contain null pointers, which are ignored. If this array
contains pointers that refer to
.BR aiocb
structures that have not been used in submitting asynchronous I/O, the
effect is undefined.
.P
If the time interval indicated in the
.BR timespec
structure pointed to by
.IR timeout
passes before any of the I/O operations referenced by
.IR list
are completed, then
\fIaio_suspend\fR()
shall return with an error.
If the Monotonic Clock option is supported, the clock that shall be
used to measure this time interval shall be the CLOCK_MONOTONIC clock.
.SH "RETURN VALUE"
If the
\fIaio_suspend\fR()
function returns after one or more asynchronous I/O operations have
completed, the function shall return zero. Otherwise, the function shall
return a value of \-1 and set
.IR errno
to indicate the error.
.P
The application may determine which asynchronous I/O completed by
scanning the associated error and return status using
\fIaio_error\fR()
and
\fIaio_return\fR(),
respectively.
.SH ERRORS
The
\fIaio_suspend\fR()
function shall fail if:
.TP
.BR EAGAIN
No asynchronous I/O indicated in the list referenced by
.IR list
completed in the time interval indicated by
.IR timeout .
.TP
.BR EINTR
A signal interrupted the
\fIaio_suspend\fR()
function. Note that, since each asynchronous I/O operation may
possibly provoke a signal when it completes, this error return may be
caused by the completion of one (or more) of the very I/O operations
being awaited.
.LP
.IR "The following sections are informative."
.SH EXAMPLES
None.
.SH "APPLICATION USAGE"
None.
.SH RATIONALE
None.
.SH "FUTURE DIRECTIONS"
None.
.SH "SEE ALSO"
.IR "\fIaio_read\fR\^(\|)",
.IR "\fIaio_write\fR\^(\|)",
.IR "\fIlio_listio\fR\^(\|)"
.P
The Base Definitions volume of POSIX.1\(hy2017,
.IR "\fB<aio.h>\fP"
.\"
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1-2017, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 7, 2018 Edition,
Copyright (C) 2018 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group.
In the event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .
.PP
Any typographical or formatting errors that appear
in this page are most likely
to have been introduced during the conversion of the source files to
man page format. To report such errors, see
https://www.kernel.org/doc/man-pages/reporting_bugs.html .
